Most white people fuck up using the word because they pause before they say it, like they're afraid of it, or are telegraphing a punch. And they only use it on rare occasions.

Just slot it right into your conversation like it ain't shit. Use it wherever you could use "guy." You wouldn't say "guy" as an insult, right? You wouldn't tell someone "YOU AIN'T NOTHIN' BUT A GUY" to piss them off. That would be stupid. So where you might say "hey, relax, guy" or "that guy don't know shit," you just say "hey, relax, nigger" or "that nigger don't know shit."

Works the other way, too. If you're afraid you'd get in trouble for using THE N-WORD, just say "guy" instead. If "guy" doesn't work for a particular sentence, then you probably shouldn't be using "nigger" there either, and it's likely that you shouldn't be saying that out loud anyway.